Fungal and fungal-like pathogens are the cause of many common plant diseases and result in losses in agricultural yield, quality and profit. Blight is an example of a plant disease that is caused by fungal or fungal-like organisms and is one of the most destructive disease of potato in Canada and worldwide.
Current agents or fungicides used to treat fungal infections include polyene antibiotics, synthetic azoles and griseofulvin. Repeated use of such fungicides results in the development of resistance by the pathogen. When fungicide resistance develops, the product or other chemically similar products no longer controls the disease effectively. Thus, new, low-toxic fungicides belonging to different chemical groups are needed to maintain control of damaging diseases caused by fungi and fungal-like organisms.
Pentacyclic triterpences such as Betulin (lup-20(29)-ene-3β,28-diol), Betulinic acid and lupeol (3β, 13ξ)-Lup-20(29)-en-3-ol) are abundant, naturally occurring triterpenes that can be isolated from plants such as white birch bark. Extracts from white birch bark have been used to treat inflammations, hepatitis, lymphatic disorders, tuberculosis cancers, and skin irritations. Moreover, pentacyclic triterpenes have been shown to have anti-viral activity against herpes simplex virus (U.S. Pat. No. 5,750,578) and to have anti-bacterial and anti-fungal activity. For example, WO 02/26761 A1 discloses the use of betulin and its derivatives as an anti-fungal agent against human pathogenic fungi Microsporum canis, Microsporum audoinii, Trichophyton mentagrophytes, Epidermophyton floccosum in in vitro growth inhibition assays performed on agar slants and in liquid cultures.
U.S. Pat. No. 6,458,834 discloses compositions comprising pentacyclic triterpenes including ursolic acid, betulin and betulinic acid for use against the plant pathogenic fungi Phytopthora infestans, Alternaria solani, Botrytis cinerea and Cersospora arachidola. 
Currently, there is a need for new anti-fungal compositions that include pentacyclic triterpenes. A need particularly exists for compositions that are effective against blight.